Fruit-fly find suggests 'extra sleep' may stall Alzheimer's disease

A new research in fruit flies has suggested that extra sleep fixes memory problems in flies with Alzheimer's-like condition

The scientists at Washington University School of Medicine in St. Louis demonstrated that extra sleep helps the brain overcome catastrophic neurological defects that otherwise would block memory formation.

Studying three groups of flies, the scientists interfered with their ability to remember by disabling a different critical memory gene in each group. In one group, the disabled gene led the flies to develop a condition with similarities to Alzheimer's disease, in another, the disabled gene made it difficult for fly brain cells to reinforce new connections that encode memories and in the third, the disrupted gene left the flies with too many of these connections.

Senior author Paul Shaw said that the data showed that extra sleep can handle any of these problems. It has to be the right kind of sleep and they're not sure how to induce this kind of slumber in human brain yet, but the research suggests that if they can learn how, it could have significant therapeutic potential.

As part of the new study, the scientists restored memory in each group of flies by using one of three techniques to increase sleep. They stimulated a cluster of key brain cells, boosted the production of a protein linked to sleep or gave the flies a drug that mimicked the activity of an important chemical messenger.

Regardless of the technique used to increase sleep, the added slumber, an extra three to four hours of sleep daily over as little as two days, restored the flies' ability to make memories.

Lead author Stephane Dissel added that in all of these flies, the lost or disabled gene still does not work properly. Sleep can't bring that missing gene back, but it finds ways to work around the physiological problem.

The study appears online in Current Biology.